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1.
Anticancer Res ; 43(6): 2741-2747, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37247924

RESUMO

BACKGROUND/AIM: The robotic retroperitoneal approach for renal mass surgery was introduced in 2018 at the Department of Urology in the clinic of Leverkusen, Germany. Clinical criteria for the choice of the access site (trans- vs. retroperitoneal) are not clearly defined. The aim of this study was to explore the learning curve and the impact of the access site on clinical outcome, in order to elucidate which preoperative clinical criteria should be taken into account when choosing the renal approach site. PATIENTS AND METHODS: This retrospective study included 107 patients who underwent robotic tumor surgery between June 2018 and March 2022 at the Department of Urology in the Clinic of Leverkusen, Germany. Data from 86 patients with transperitoneal robotic surgery of the kidney and 21 patients with retroperitoneal access were available for analysis. We evaluated the data of patients in a trans- and a retroperitoneal access group. The preoperative clinical data included anthropomorphic data, the Body Mass Index (BMI) as well as the Preoperative Aspects and Dimensions Used for Anatomical Classification of Renal Masses (PADUA) - score. Intraoperative and postoperative data such as blood loss, clamping time, renal function and the learning curve of the surgeons was used to evaluate the outcomes of the two groups. RESULTS: Operation time in the retroperitoneal group was significantly shorter (p=0.015). Operation-specific variables showed no significant difference between the two groups. PADUA score and hilar clamping time showed no difference (p=0.345 and p=0.130, respectively). The learning curve in the retroperitoneal access group unveiled a noticeable difference in the experience and mastery of the involved surgeons. CONCLUSION: Mastery of the retroperitoneal approach is readily possible for surgeons with previous experience in robotic renal surgery without compromising the operative morbidity. The PADUA-score seems most suitable as a preoperative clinical criterion for choosing the renal approach site.


Assuntos
Neoplasias Renais , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Estudos Retrospectivos , Curva de Aprendizado , Resultado do Tratamento , Nefrectomia/métodos , Espaço Retroperitoneal/cirurgia , Espaço Retroperitoneal/patologia , Laparoscopia/métodos
2.
J Clin Med ; 11(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36078994

RESUMO

BACKGROUND: Hybrid imaging with prostate-specific membrane antigen (PSMA) is gaining importance as an increasingly meaningful tool for prostate cancer (PC) diagnostics and as a guide for therapy decisions. This study aims to investigate and compare the performance of [18F]PSMA-1007 (18F-PSMA) and [68Ga]Ga-PSMA-11 positron emission tomography/computed tomography (68Ga-PSMA) in the initial staging of PC patients. METHODS: The data of 88 biopsy-proven patients were retrospectively evaluated. PSMA-avid lesions were compared with the histopathologic Gleason Score (GS) for prostate biopsies, and the results were plotted by receiver operating characteristic (ROC)-curve. Optimal maximum standardized uptake value (SUVmax) cut-off values were rated using the Youden index. RESULTS: 18F-PSMA was able to distinguish GS ≤ 7a from ≥7b with a sensitivity of 62%, specificity of 85%, positive predictive value (PPV) of 92%, and accuracy of 67% for a SUVmax of 8.95, whereas sensitivity was 54%, specificity 91%, PPV 93%, and accuracy 66% for 68Ga-PSMA (SUVmax 8.7). CONCLUSIONS: Both methods demonstrated a high concordance of detected PSMA-avid lesions with histopathologically proven PC. 18F-PSMA and 68Ga-PSMA are both suitable for the characterization of primary PC with a comparable correlation of PSMA-avid lesions with GS. Neither method showed a superior advantage. Our calculated SUVmax thresholds may represent valuable parameters in clinical use to distinguish clinically significant PC (csPC) from non-csPC.

3.
Cancers (Basel) ; 14(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35326629

RESUMO

This study aimed to compare the diagnostic performance of [18F]PSMA-1007 positron emission tomography/computed tomography (PET/CT) (18F-PSMA) and [68Ga]Ga-PSMA-11 PET/CT (68Ga-PSMA) by identifying prostate-specific antigen (PSA) threshold levels for optimal detecting recurrent prostate cancer (PC) and to compare both methods. Retrospectively, the study included 264 patients. The performances of 18F-PSMA and 68Ga-PSMA in relation to the pre-scan PSA were assessed by receiver operating characteristic (ROC) curve. 18F-PSMA showed PC-lesions in 87.5% (112/128 patients), while 68Ga-PSMA identified them in 88.9% (121/136). For 18F-PSMA biochemical recurrent (BCR) patients treated with radical prostatectomy (78/128, patient group: F-RP), a PSA of 1.08 ng/mL was found to be the optimal cut-off level for predicting positive and negative scans (AUC = 0.821; 95%, CI: 0.710−0.932), while for prostatectomized 68Ga-PSMA BCR-patients (89/136, patient group: Ga-RP), the cut-off was 1.84 ng/mL (AUC = 0.588; 95%, CI: 0.410−0.766). In patients with PSA < 1.08 ng/mL (F-RP) 76.3% and <1.84 ng/mL (Ga-RP) 78.6% scans were positive, whereas patients with PSA ≥ 1.08 ng/mL (F-RP) or 1.84 ng/mL (Ga-RP) had positive scan results in 100% and 91.5% (p < 0.001/p = 0.085). The identified PSA thresholds for PSMA-mappable PC lesions in BCR-patients (RP) showed a better separation for 18F-PSMA with regard to the distinguishing of positive and negative PC-lesions compared to 68Ga-PSMA. However, the two PSMA PET/CT tracers gave similar overall findings.

4.
Urol Int ; 106(10): 1061-1067, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34130302

RESUMO

INTRODUCTION: The impact of teratomatous elements in orchiectomy specimens of metastasized testicular germ cell tumors (TGCT) regarding oncological outcome is still unclear. METHODS: We performed a retrospective analysis including 146 patients with metastasized TGCT analysing patient characteristics. RESULTS: Twenty-six (18%) of all patients showed teratomatous elements in the orchiectomy specimens. TGCT with teratomatous elements showed a significantly higher frequency of clinical-stage 2C-3 disease (73 vs. 49%, p = 0.031), visceral metastases (58 vs. 32%, p = 0.015), and poor prognosis (p = 0.011) than TGCT without teratomatous elements. Teratoma-containing TGCT revealed a significantly higher rate of post-chemotherapy retroperitoneal lymph node dissection (PC-RPLND, 54 vs. 32%, p = 0.041), with teratomatous elements being more often present in the PC-RPLND specimens (43 vs. 11%, p = 0.020) than nonteratoma-containing primaries. In the Kaplan-Meier estimates, the presence of teratomatous elements in orchiectomy specimens was associated with a significantly reduced relapse-free survival (RFS) (p = 0.049) during a median follow-up of 36 months (10-115.5). CONCLUSIONS: The presence of teratomatous elements in orchiectomy specimens is associated with an advanced tumor stage, worse treatment response as well as a reduced RFS in metastasized TGCT. Consequently, the presence of teratomatous elements might act as a reliable stratification tool for treatment decision in TGCT patients.


Assuntos
Neoplasias Embrionárias de Células Germinativas , Teratoma , Neoplasias Testiculares , Humanos , Excisão de Linfonodo , Metástase Linfática , Masculino , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Orquiectomia , Espaço Retroperitoneal , Estudos Retrospectivos , Teratoma/cirurgia , Neoplasias Testiculares/patologia
5.
Anticancer Res ; 41(11): 5585-5591, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34732429

RESUMO

BACKGROUND/AIM: Predictors for complications such as insufficiency of intestinal anastomosis in urinary diversion and other risk factors are not well defined. We aimed to elucidate predictive factors for complications in urinary diversions based on preoperative comorbidities and major complications. A special focus was set on anastomosis insufficiency as a major complication. PATIENTS AND METHODS: Preoperative comorbidities, postoperative complications, duration of hospital stay, and follow-up were analyzed in 317 patients with urinary diversion. The impact of preoperative comorbidities on diversion types was described and quantified as defined by the age-adjusted Charlson Comorbidity Index. RESULTS: Overall, 14.8% of patients showed anastomosis-related complications, most within the ileal conduit group (15.9% in the cohort). Severe complications (Clavien-Dindo Classification Score >IIIa) were found in smokers (p=0.046), and in patients with vascular diseases (p=0.007), a high American Society of Anaesthesiologists (ASA)-score (p=0.047), a R1- (p=0.009), as well as a pN1 (p=0.007) status. CONCLUSION: Several independent predictors for several postoperative complications in urinary diversions were identified, which were independent of the diversion method.


Assuntos
Cistectomia , Complicações Pós-Operatórias/etiologia , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária/efeitos adversos , Fatores Etários , Idoso , Comorbidade , Cistectomia/efeitos adversos , Bases de Dados Factuais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia
6.
Invest New Drugs ; 39(4): 914-927, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33492639

RESUMO

Introduction Differentiation therapy is a promising strategy for cancer treatment. The translationally controlled tumor protein (TCTP) is an encouraging target in this context. By now, this field of research is still at its infancy, which motivated us to perform a large-scale screening for the identification of novel ligands of TCTP. We studied the binding mode and the effect of TCTP blockade on the cell cycle in different cancer cell lines. Methods Based on the ZINC-database, we performed virtual screening of 2,556,750 compounds to analyze the binding of small molecules to TCTP. The in silico results were confirmed by microscale thermophoresis. The effect of the new ligand molecules was investigated on cancer cell survival, flow cytometric cell cycle analysis and protein expression by Western blotting and co-immunoprecipitation in MOLT-4, MDA-MB-231, SK-OV-3 and MCF-7 cells. Results Large-scale virtual screening by PyRx combined with molecular docking by AutoDock4 revealed five candidate compounds. By microscale thermophoresis, ZINC10157406 (6-(4-fluorophenyl)-2-[(8-methoxy-4-methyl-2-quinazolinyl)amino]-4(3H)-pyrimidinone) was identified as TCTP ligand with a KD of 0.87 ± 0.38. ZINC10157406 revealed growth inhibitory effects and caused G0/G1 cell cycle arrest in MOLT-4, SK-OV-3 and MCF-7 cells. ZINC10157406 (2 × IC50) downregulated TCTP expression by 86.70 ± 0.44% and upregulated p53 expression by 177.60 ± 12.46%. We validated ZINC10157406 binding to the p53 interaction site of TCTP and replacing p53 by co-immunoprecipitation. Discussion ZINC10157406 was identified as potent ligand of TCTP by in silico and in vitro methods. The compound bound to TCTP with a considerably higher affinity compared to artesunate as known TCTP inhibitor. We were able to demonstrate the effect of TCTP blockade at the p53 binding site, i.e. expression of TCTP decreased, whereas p53 expression increased. This effect was accompanied by a dose-dependent decrease of CDK2, CDK4, CDK, cyclin D1 and cyclin D3 causing a G0/G1 cell cycle arrest in MOLT-4, SK-OV-3 and MCF-7 cells. Our findings are supposed to stimulate further research on TCTP-specific small molecules for differentiation therapy in oncology.


Assuntos
Antineoplásicos/farmacologia , Drogas em Investigação/farmacologia , Neoplasias/tratamento farmacológico , Proteína Tumoral 1 Controlada por Tradução/antagonistas & inibidores , Antineoplásicos/administração & dosagem , Artesunato/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Simulação por Computador , Bases de Dados de Produtos Farmacêuticos , Relação Dose-Resposta a Droga , Drogas em Investigação/administração & dosagem , Humanos , Ligantes , Simulação de Acoplamento Molecular , Neoplasias/patologia , Proteína Tumoral 1 Controlada por Tradução/metabolismo
7.
Chem Biol Interact ; 334: 109349, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33259807

RESUMO

INTRODUCTION: Cancer is one of the leading causes of death worldwide. Classical cytotoxic chemotherapy exerts high side effects and low tumor selectivity. Translationally controlled tumor protein (TCTP) is a target for differentiation therapy, a promising, new therapeutic approach, which is expected to be more selective and less toxic than cytotoxic chemotherapy. The aim of the present investigation was to identify novel TCTP inhibitors. METHODS: We performed in silico screening and molecular docking using a chemical library of more than 31,000 compounds to identify a novel inhibitor of TCTP. We tested AMG900 in vitro for binding to TCTP by microscale thermophoresis and co-immunoprecipitation. Additionally, we examined the effect of TCTP blockade on cell cycle progression by flow cytometry and Western blotting and cancer cell survival by resazurin assays in MCF-7, SK-OV3 and MOLT-4 cell lines. RESULTS: We identified AMG900 as new inhibitor of TCTP. AMG900 bound to the p53 binding site of TCTP with a free binding energy of -9.63 ±â€¯0.01 kcal/mol. This compound decreased TCTP expression to 23.4 ±â€¯1.59% and increased p53 expression to 194.29 ±â€¯24.27%. Furthermore, AMG900 induced G0/G1 arrest as shown by flow cytometry and Western blot of relevant cell cycle proteins. AMG900 decreased CDK2, CDK4, CDK6, cyclin D1 and cyclin D3 expression, whereas p18, p21 and p27 expression increased. Moreover, AMG900 disturbed TCTP-p53 complexation as shown by co-immunoprecipitation and increased expression of free p53. DISCUSSION: AMG900 may serve as novel lead compound for the development of differentiation therapy approaches against cancer.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Ftalazinas/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Fase G1/efeitos dos fármacos , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Proteína Tumoral 1 Controlada por Tradução
8.
Cancers (Basel) ; 12(10)2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998432

RESUMO

Routine [68Ga]Ga-PSMA-11 PET/CT (one hour post-injection) has been shown to accurately detect prostate cancer (PCa) lesions. The goal of this study is to evaluate the benefit of a dual-time point imaging modality for the staging and restaging of PCa patients. Biphasic [68Ga]Ga-PSMA-11 PET/CT of 233 patients, who underwent early and late scans (one/three hours post-injection), were retrospectively studied. Tumor uptake and biphasic lesion detection for 215 biochemically recurrent patients previously treated for localized PCa (prostatectomized patients (P-P)/irradiated patients (P-I) and 18 patients suspected of having primary PCa (P-T) were separately evaluated. Late [68Ga]Ga-PSMA-11 PET/CT imaging detected 554 PCa lesions in 114 P-P patients, 187 PCa lesions in 33 P-I patients, and 47 PCa lesions in 13 P-T patients. Most patients (106+32 P-P/P-I, 13 P-T) showed no additional PCa lesions. However, 11 PSMA-avid lesions were only detected in delayed images, and 33 lesions were confirmed as malignant by a SUVmax increase. The mean SUVmax of pelvic lymph node metastases was 25% higher (p < 0.001) comparing early and late PET/CT. High positivity rates from routine [68Ga]Ga-PSMA-11 PET/CT for the staging and restaging of PCa patients were demonstrated. There was no decisive influence of additional late imaging with PCa lesion detection on therapeutic decisions. However, in a few individual cases, additional delayed scans provided an information advantage in PCa lesion detection due to higher tracer uptake and improved contrast.

9.
Cancers (Basel) ; 12(2)2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32046318

RESUMO

68Ga-PSMA-11 positron-emission tomography/computed tomography (PET/CT) is commonly used for restaging recurrent prostate cancer (PC) in European clinical practice. The goal of this study is to determine the optimum time for performing these PET/CT scans in a large cohort of patients by identifying the prostate-specific-antigen (PSA) and PSA kinetics thresholds for detecting and localizing recurrent PC. This retrospective analysis includes 581 patients with biochemical recurrence (BC) by definition. The performance of 68Ga-PSMA-11 PET/CT in relation to the PSA value at the scan time as well as PSA kinetics was assessed by the receiver-operating-characteristic-curve (ROC) generated by plotting sensitivity versus 1-specificity. Malignant prostatic lesions were identified in 77%. For patients that were treated with radical prostatectomy (RP) a PSA value of 1.24 ng/mL was found to be the optimal cutoff level for predicting positive and negative scans, while for patients previously treated with radiotherapy (RT) it was 5.75 ng/mL. In RP-patients with PSA value <1.24 ng/mL, 52% scans were positive, whereas patients with PSA ≥1.24 ng/mL had positive scan results in 87%. RT-patients with PSA <5.75 ng/mL had positive scans in 86% and and for those with PSA ≥5.75 ng/mL 94% had positive scans. This study identifies the PSA and PSA kinetics threshold levels for the presence of 68Ga-PSMA-11 PET/CT-detectable PC-lesions in BC patients.

10.
EXCLI J ; 18: 1071-1091, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31839763

RESUMO

Primary human hepatocytes (PHHs) remain the gold standard for in vitro investigations of xenobiotic metabolism and hepatotoxicity. However, scarcity of liver tissue and novel developments in liver surgery has limited the availability and quality of tissue samples. In particular, warm ischemia shifts the intracellular metabolism from aerobic to anaerobic conditions, which increases glycogenolysis, glucose depletion and energy deficiency. Therefore, the aim of the present study was to investigate whether supplementation with glucose and insulin during PHH isolation could reconstitute intracellular glycogen storage and beneficially affect viability and functionality. Furthermore, the study elucidated whether the susceptibility of the tissue's energy status correlates with body mass index (BMI). PHHs from 12 donors were isolated from human liver tissue obtained from partial liver resections using a two-step EDTA/collagenase perfusion technique. For a direct comparison of the influence of glucose/insulin supplementation, we modified the setup, enabling the parallel isolation of two pieces of one tissue sample with varying perfusate. Independent of the BMI of the patient, the glycogen content in liver tissue was notably low in the majority of samples. Furthermore, supplementation with glucose and insulin had no beneficial effect on the glycogen concentration of isolated PHHs. However, an indirect improvement of the availability of energy was shown by increased viability, plating efficiency and partial cellular activity after supplementation. The plating efficiency showed a striking inverse correlation with increasing lipid content of PHHs. However, 60 h of cultivation time revealed no significant impact on the maintenance of albumin and urea synthesis or xenobiotic metabolism after supplementation. In conclusion, surgical procedures and tissue handling may decrease hepatic energy resources and lead to cell stress and death. Consequently, PHHs with low energy resources die during the isolation process without supplementation of glucose/insulin or early cell culture, while their survival rates are improved with glucose/insulin supplementation.

11.
J Vasc Interv Radiol ; 30(9): 1452-1458, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31371137

RESUMO

PURPOSE: To evaluate the radiation dose in patients undergoing prostatic artery embolization (PAE) using cone-beam CT and 3-dimensional (3D) guidance software. MATERIALS AND METHODS: In this single-center retrospective study, 100 patients with benign prostatic hyperplasia (mean prostate volume, 83.6 mL ± 44.2; 69.4 ± 9.6 years of age; body mass index, 26.5 ± 4.2) were treated using PAE between October 2016 and April 2018. Informed consent was obtained from all participants included in the study. All patients received at least 1 intraprocedural cone-beam CT per side for evaluation of the vessel anatomy and software rendering of 3D guidance for catheter guidance. Digital subtraction angiography (DSA) was performed in the distal branches only. The total dose area product (DAP), along with the DAP attributed to fluoroscopy, DSA, and cone-beam CT, were assessed. RESULTS: Bilateral embolization was achieved in 83 patients (83%). The average total DAP was 134.4 Gy ⋅ cm2 ± 69.5 (range, 44.7-410.9 Gy ⋅ cm2). Fluoroscopy, DSA, and cone-beam CT accounted for 35.5 Gy ⋅ cm2 ± 21.3 (range, 8.6-148.6 Gy ⋅ cm2) or 26.4% (percentage of total DAP), 58.2 Gy ⋅ cm2 ± 48.3 (range, 10.3-309.3 Gy ⋅ cm2) or 43.3%, and 40.7 Gy ⋅ cm2 ± 14.5 (range, 15.9-86.3 Gy ⋅ cm2) or 30.3%, respectively. Average procedure time was 89.4 ± 27.0 minutes, and the average fluoroscopy time was 30.9 ± 12.2 minutes. CONCLUSIONS: Intraprocedural cone-beam CT in combination with 3D guidance software allows for identification and catheterization of the prostatic artery in PAE. Furthermore, the results of this trial indicate that this study protocol may lead to a low overall radiation dose.


Assuntos
Artérias/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Tomografia Computadorizada de Feixe Cônico , Embolização Terapêutica , Imageamento Tridimensional , Próstata/irrigação sanguínea , Hiperplasia Prostática/terapia , Doses de Radiação , Radiografia Intervencionista/métodos , Software , Idoso , Angiografia por Tomografia Computadorizada/efeitos adversos , Tomografia Computadorizada de Feixe Cônico/efeitos adversos , Embolização Terapêutica/efeitos adversos , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Hiperplasia Prostática/diagnóstico por imagem , Exposição à Radiação , Radiografia Intervencionista/efeitos adversos , Estudos Retrospectivos , Medição de Risco , Fatores de Tempo
12.
Phytomedicine ; 47: 192-200, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30166104

RESUMO

BACKGROUND: Radiotherapy is a mainstay of cancer treatment since decades. Ionizing radiation (IR) is used for destruction of cancer cells and shrinkage of tumors. However, the increase of radioresistance in cancer cells and radiation toxicity to normal tissues are severe concerns. The exposure to radiation generates intracellular reactive oxygen species (ROS), which leads to DNA damage by lipid peroxidation, removal of thiol groups from cellular and membrane proteins, strand breaks and base alterations. HYPOTHESIS: Plants have to deal with radiation-induced damage (UV-light of sun, other natural radiation sources). Therefore, it is worth speculating that radioprotective mechanisms have evolved during evolution of life. We hypothesize that natural products from plants may also protect from radiation damage caused as adverse side effects of cancer radiotherapy. METHODS: The basis of this systematic review, we searched the relevant literature in the PubMed database. RESULTS: Flavonoids, such as genistein, epigallocatechin-3-gallate, epicatechin, apigenin and silibinin mainly act as antioxidant, free radical scavenging and anti-inflammatory compounds, thus, providing cytoprotection in addition to downregulation of several pro-inflammatory cytokines. Comparable effects have been found in phenylpropanoids, especially caffeic acid phenylethylester, curcumin, thymol and zingerone. Besides, resveratrol and quercetin are the most important cytoprotective polyphenols. Their radioprotective effects are mediated by a wide range of mechanisms mainly leading to direct or indirect reduction of cellular stress. Ascorbic acid is broadly used as antioxidant, but it has also shown activity in reducing cellular damage after irradiation mainly due to its antioxidant capabilities. The metal ion chelator, gallic acid, represents another natural product attenuating cellular damage caused by radiation. CONCLUSIONS: Some secondary metabolites from plants reveal radioprotective features against cellular damage caused by irradiation. These results warrant further analysis to develop phytochemicals as radioprotectors for clinical use.


Assuntos
Compostos Fitoquímicos/farmacologia , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Radioterapia/efeitos adversos , Antioxidantes/farmacologia , Ácido Ascórbico , Curcumina/farmacologia , Dano ao DNA/efeitos dos fármacos , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Humanos , Peroxidação de Lipídeos , Neoplasias/radioterapia , Plantas/química , Polifenóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Resveratrol , Estilbenos/farmacologia
14.
Mol Cancer Ther ; 17(8): 1739-1751, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29743205

RESUMO

CD47, an ubiquitously expressed innate immune checkpoint receptor that serves as a universal "don't eat me" signal of phagocytosis, is often upregulated by hematologic and solid cancers to evade immune surveillance. Development of CD47-targeted modalities is hindered by the ubiquitous expression of the target, often leading to rapid drug elimination and hemotoxicity including anemia. To overcome such liabilities, we have developed a fully human bispecific antibody, NI-1701, designed to coengage CD47 and CD19 selectively on B cells. NI-1701 demonstrates favorable elimination kinetics with no deleterious effects seen on hematologic parameters following single or multiple administrations to nonhuman primates. Potent in vitro and in vivo activity is induced by NI-1701 to kill cancer cells across a plethora of B-cell malignancies and control tumor growth in xenograft mouse models. The mechanism affording maximal tumor growth inhibition by NI-1701 is dependent on the coengagement of CD47/CD19 on B cells inducing potent antibody-dependent cellular phagocytosis of the targeted cells. NI-1701-induced control of tumor growth in immunodeficient NOD/SCID mice was more effective than that achieved with the anti-CD20 targeted antibody, rituximab. Interestingly, a synergistic effect was seen when tumor-implanted mice were coadministered NI-1701 and rituximab leading to significantly improved tumor growth inhibition and regression in some animals. We describe herein, a novel bispecific antibody approach aimed at sensitizing B cells to become more readily phagocytosed and eliminated thus offering an alternative or adjunct therapeutic option to patients with B-cell malignancies refractory/resistant to anti-CD20-targeted therapy. Mol Cancer Ther; 17(8); 1739-51. ©2018 AACR.


Assuntos
Anticorpos Biespecíficos/genética , Leucemia/genética , Leucemia/terapia , Linfoma de Células B/genética , Linfoma de Células B/terapia , Animais , Antígenos CD19 , Antígeno CD47 , Humanos , Leucemia/patologia , Linfoma de Células B/patologia , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Antibodies (Basel) ; 7(1)2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31544856

RESUMO

CD47 serves as an anti-phagocytic receptor that is upregulated by cancer to promote immune escape. As such, CD47 is the focus of intense immuno-oncology drug development efforts. However, as CD47 is expressed ubiquitously, clinical development of conventional drugs, e.g., monoclonal antibodies, is confronted with patient safety issues and poor pharmacology due to the widespread CD47 "antigen sink". A potential solution is tumor-directed blockade of CD47, which can be achieved with bispecific antibodies (biAbs). Using mouse CD47-blocking biAbs in a syngeneic tumor model allowed us to evaluate the efficacy of tumor-directed blockade of CD47 in the presence of the CD47 antigen sink and a functional adaptive immune system. We show here that CD47-targeting biAbs inhibited tumor growth in vivo, promoting durable antitumor responses and stimulating CD8+ T cell activation in vitro. In vivo efficacy of the biAbs could be further enhanced when combined with chemotherapy or PD-1/PD-L1 immune checkpoint blockade. We also show that selectivity and pharmacological properties of the biAb are dependent on the affinity of the anti-CD47 arm. Taken together, our study validates the approach to use CD47-blocking biAbs either as a monotherapy or part of a multi-drug approach to enhance antitumor immunity.

16.
Antibodies (Basel) ; 7(3)2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31544881

RESUMO

Bispecific antibodies (bsAbs) are often composed of several polypeptide chains that have to be expressed adequately to enable optimal assembly and yield of the bsAb. κλ bodies are a bispecific format with a native IgG structure, composed of two different light chains that pair with a common heavy chain. Introduction of non-optimal codons into the sequence of a particular polypeptide is an effective strategy for down modulating its expression. Here we applied this strategy but restricted the modification of the codon content to the constant domain of one light chain. This approach facilitates parallel optimization of several bsAbs by using the same modified constant domains. Partial sequence de-optimization reduced expression of the targeted polypeptide. Stable cell pools could be isolated displaying increased bispecific antibody titers as well as changes in the abundance of undesired by-products that require elimination during downstream processing. Thus, modulating the relative expression of polypeptides can have a significant impact on bsAb titer and product related impurities; which are important factors for large scale manufacturing for clinical supply.

17.
Phytother Res ; 32(2): 185-198, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29044858

RESUMO

Medicinal plants have always had great value for the human population due to their valuable constituents and potential bioactivities. The objective of this review is to present an updated overview of an important medicinal plant genus Nepeta L., from the family Lamiaceae, revealing its traditional utilization, biological activity, phytoconstituents, and mechanisms of action. For this purpose, a literature survey was carried out by using SciFinder, ScienceDirect, Scopus, PubMed, and Web of Science followed by a revision of the bibliographies of the related articles. We have described and analyzed the role of plants in drug discovery and the importance of Nepeta species. Information on the utilization purposes of Nepeta species in folk medicine has been emphasized, and scientific studies on the biological effects and secondary metabolites are addressed. Nepeta species are characterized by terpenoid-type compounds and phenolic constituents, which exert several activities such as an antimicrobial, repellent against major pathogen vector mosquitoes, insecticide, larvicide against Anopheles stephensi, cytotoxic anticarcinogen, antioxidant, anticonvulsant, analgesic, anti-inflammatory agent, and antidepressant, revealing its importance in medicinal and agricultural fields. On the basis of numerous studies, the Nepeta genus demonstrates remarkable therapeutic effects against various diseases. However, clinical studies are warranted to confirm preclinical findings.


Assuntos
Medicina Tradicional/métodos , Nepeta/química , Fitoterapia/métodos , Plantas Medicinais/efeitos dos fármacos , Humanos
18.
Pharmacol Res ; 129: 262-273, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29179999

RESUMO

Alzheimer's disease (AD) is the most prevalent form of dementia. The exact pathophysiology of this disease remains incompletely understood and safe and effective therapies are required. AD is highly correlated with neuroinflammation and oxidative stress in brain causing neuronal loss. Nuclear factor of activated B-cells (NF-κB) is involved in physiological inflammatory processes and thus representing a promising target for inflammation-based AD therapy. Phytochemicals are able to interfere with the NF-κB pathway. They inhibit the phosphorylation or the ubiquitination of signaling molecules, and thus, inhibit the degradation of IκB. The translocation of NF-κB to the nucleus and subsequent transcription of pro-inflammatory cytokines are inhibited by the actions of phytochemicals. Additionally, natural compounds preventing the interaction of NF-κB can block NF-κB's transcriptional activity by inhibiting its binding to target DNA. Many polyphenols including curcumin, resveratrol, pterostilbene, punicalagin, macranthoin G, salidroside, 4-O-methylhonokiol, lycopene, genistein, obovatol and gallic acid were reported as potent NF-κB inhibitors for AD treatment. Several alkaloids such as galantamine, glaucocalyxin B, tetrandrine, berberine, oridonin, anatabine have been shown anti-inflammatory effects in AD models in vitro as well as in vivo. Besides, vitamins, tanshinone IIA, artemisinin, dihydroasparagusic acid, geniposide, xanthoceraside, l-theranine, 1,8-cineole and paeoniflorin were described as promising NF-κB inhibitors. In conclusion, natural products from plants represent interesting candidates for AD treatment. They may qualify as promising compounds for the development of derivatives providing enhanced pharmacological features.


Assuntos
Alcaloides/farmacologia , Doença de Alzheimer/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Compostos Fitoquímicos/farmacologia , Polifenóis/farmacologia , Animais , Humanos , Vitaminas/farmacologia
19.
Results Probl Cell Differ ; 64: 263-281, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29149414

RESUMO

The translationally controlled tumor protein (TCTP) is a highly conserved protein that is regulated due to a high number of extracellular stimuli. TCTP has an important role for cell cycle and normal development. On the other side, tumor reversion and malignant transformation have been associated with TCTP. TCTP has been found among the 12 genes that are differentially expressed during mouse oocyte maturation, and an overexpression of this gene was reported in a wide variety of different cancer types. Its antiapoptotic effect is indicated by the interaction with several proapoptotic proteins of the Bcl-2 family and the p53 tumor suppressor protein. In this article, we draw attention to the role of TCTP in cancer, especially, focusing on cell differentiation and tumor reversion, a biological process by which highly tumorigenic cells lose their malignant phenotype. This protein has been shown to be the most strongly downregulated protein in revertant cells compared to the parental cancer cells. Decreased expression of TCTP results either in the reprogramming of cancer cells into reversion or apoptosis. As conventional chemotherapy is frequently associated with the development of drug resistance and high toxicity, the urge for the development of new or additional scientific approaches falls into place. Differentiation therapy aims at reinducing differentiation backward to the nonmalignant cellular state. Here, different approaches have been reported such as the induction of retinoid pathways and the use of histone deacetylase inhibitors. Also, PPARγ agonists and the activation of the vitamin D receptor have been reported as potential targets in differentiation therapy. As TCTP is known as the histamine-releasing factor, antihistaminic drugs have been shown to target this protein. Antihistaminic compounds, hydroxyzine and promethazine, inhibited cell growth of cancer cells and decreased TCTP expression of breast cancer and leukemia cells. Recently, we found that two antihistaminics, levomepromazine and buclizine, inhibited cancer cell growth by direct binding to TCTP and induction of cell differentiation. These data confirmed that TCTP is an exquisite target for anticancer differentiation therapy and antihistaminics have potential to be lead compounds for the direct interaction with TCTP as new inhibitors of human TCTP and tumor growth.


Assuntos
Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/metabolismo , Diferenciação Celular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos/uso terapêutico , Humanos , Camundongos , Proteína Tumoral 1 Controlada por Tradução
20.
Protein Eng Des Sel ; 30(9): 575-582, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28444391

RESUMO

Antibody phage display technology has supported the emergence of numerous therapeutic antibodies. The development of bispecific antibodies, a promising new frontier in antibody therapy, could be facilitated by new phage display approaches that enable pairs of antibodies to be co-selected based on co-engagement of their respective targets. We describe such an approach, making use of two complementary leucine zipper domains that heterodimerize with high affinity. Phagemids encoding a first antibody fragment (scFv) fused to phage coat protein via the first leucine zipper are rescued in bacteria expressing a second scFv fused to the second leucine zipper as a soluble periplasmic protein, so that it is acquired by phage during assembly. Using a soluble scFv specific for a human CD3-derived peptide, we show that its acquisition by phage displaying an irrelevant antibody is sufficiently robust to drive selection of rare phage (1 in 10(5)) over three rounds of panning. We then set up a model selection experiment using a cell line expressing the chemokine receptor CCR5 fused to the CD3 peptide together with a panel of phage clones capable displaying either an anti-CCR5 scFv or an irrelevant antibody, with or without the capacity to acquire the soluble anti-CD3 scFv. In this experiment we showed that rare phage (1 in 10(5)) capable of displaying the two different scFvs can be specifically enriched over four rounds of panning. This approach has the potential to be applied to the identification of pairs of ligands capable of co-engaging two different user-defined targets, which would facilitate the discovery of novel bispecific antibodies.


Assuntos
Anticorpos Biespecíficos/biossíntese , Anticorpos Monoclonais/biossíntese , Bacteriófagos/genética , Biblioteca de Peptídeos , Proteínas Recombinantes de Fusão/genética , Anticorpos de Cadeia Única/biossíntese , Sequência de Aminoácidos , Animais , Anticorpos Biespecíficos/genética , Anticorpos Monoclonais/genética , Especificidade de Anticorpos , Bacteriófagos/imunologia , Complexo CD3/genética , Complexo CD3/imunologia , Células CHO , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Cricetulus , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/virologia , Expressão Gênica , Humanos , Zíper de Leucina , Peptídeos/genética , Peptídeos/imunologia , Receptores CCR5/genética , Receptores CCR5/imunologia , Proteínas Recombinantes de Fusão/imunologia , Análise de Sequência de DNA , Anticorpos de Cadeia Única/genética
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